碟盘刀具上刀齿切削煤岩的载荷特性研究

Study on load characteristics of cutting coal and rock with cutter tooth on disk cutter

为探求碟盘刀具切削煤岩载荷规律和高效破碎煤岩机构特性评价方法,采用碟盘刀具结构简化处理方法,以一个刀齿作为等效分析单元,在载荷理论模型构建中,给出了等效切削厚度的概念和算法,以数值模拟、试验和理论方法获取了刀齿切削煤岩的载荷曲线,探讨轴向振动径向切削煤岩载荷特性和对比特征。结果表明:刀齿径向切削数值模拟、试验和理论载荷随楔面角的变化规律是吻合的,验证了刀齿径向切削煤岩力学模型的正确性,其理论径向载荷与试验最大值和平均值分别减小5%和增大14%,轴向载荷均值理论与试验均值减小19.5%,轴向载荷方向呈现正负的变化,当完全楔入煤岩中,轴向载荷方向呈现由向下变为向上的变化规律。类比分析了刀齿轴向向上振动与径向复合切削,其径向载荷理论值比径向切削试验均值减少了约32%,而轴向载荷比试验均值减少了约27%。碟盘刀具轴向振动径向复合切削方法破碎煤岩特性的研究,为研制硬岩破碎机构提供技术参考。

In order to explore the law of cutting coal-rock load and the evaluation method of high-efficiency fractured coal and rock mechanism,the simplified method of disk cutter structure is adopted,and the single tooth in disk plate is used as the equivalent analysis unit.In the construction of load theory model,the concept and algorithm of effective cutting thickness were obtained by numerical simulation,experimental and theoretical methods.The load curves of the cutting coal and rock were obtained by numerical simulation test and theoretical method,and the load characteristics and contrast characteristics of the radial cutting coal rock were diskussed.The results show that the numerical simulation,experimental and theoretical loads of the cutter teeth were consistent with the variation of the wedge angle,which verifies the correctness of the mechanical model of radial cutting coal.The theoretical radial load and the experimental maximum were obtained,and the average of the two decreased by 5%and increased by 14%respectively,the axial load mean theory and the test mean decreased by 19.5%,and the axial load direction showed positive and negative changes,and when fully wedged into the coal rock,the axial load direction was changed from downward to upward.The theoretical value of radial load is about 32%less than that of radial cutting test,and the axial load is about 27%less than the average test mean.The study on characteristics of fractured coal rock of axial vibration radial composite cutting method has practical significance for development of hard rock crushing mechanism.